1. Field of the Invention
The present invention relates to generally to sealing machines and processes, and more particularly to machines and processes for sealing epoxy sticks in plastic.
2. Description of the Prior Art
Wrapping epoxy sticks is an important aspect of delivering epoxy stick products to an end user. Without proper wrapping, epoxy sticks can dry out and become useless. Yet, prior to the present invention, wrapping an epoxy stick was a time-consuming and expensive process. Formerly, conventional practice was to place foil disks on ends of an epoxy stick, and then wrap the stick in plastic wrapping material. Because this conventional process is both expensive and time-consuming, a new method is needed that does not require use of foil disks and that can use inexpensive polyethylene wrapping. Other sealing processes have been developed, but none provides the desirable epoxy-stick wrapping characteristics of the present invention.
U.S. Pat. No. 1,887,844, issued on Nov. 15, 1932, to Francis X. Malocsay, describes a sealing device for cigar-wrapping machines. The device heat-seals twisted ends of cigar wrappers. This patent does not show spatially adjustable heating elements, adjustable-speed conveyor belts, or the technique of orienting polyethylene wrappers with a grain parallel to a long axis of a wrapped cylindrical object.
U.S. Pat. No. 2,581,309, issued on Jan. 1, 1952, to Constantine S. Stephano, describes a relatively complicated mechanism for first folding and then heat-sealing ends of cigarette wrappers. This patent does not show spatially adjustable heating elements, adjustable-speed conveyor belts, or the technique of orienting polyethylene wrappers with a grain parallel to a long axis of a wrapped cylindrical object.
U.S. Pat. No. 3,432,982, issued on Mar. 18, 1969, to Friedheim Brinkmeier et al., describes a bag-sealing device which requires cleaning of bag-portions to be sealed, prior to sealing. This patent does not show spatially adjustable heating elements, adjustable-speed conveyor belts, or the technique of orienting polyethylene wrappers with a grain parallel to a long axis of a wrapped cylindrical object.
U.S. Pat. No. 3,629,993, issued on Dec. 28, 1971, to Albert H. Chant, Jr., describes a wrapping devices which requires gripper chains to stretch film to be heat sealed. This patent does not show spatially adjustable heating elements, adjustable-speed conveyor belts, or the technique of orienting polyethylene wrappers with a grain parallel to a long axis of a wrapped cylindrical object.
U.S. Pat. No. 4,225,318, issued on Sept. 30, 1980, to Hank J. Wrigley, Jr., shows a sealed package but does not describe sealing methods or apparatus. There is a wick hermetically sealed between two layers of plastic, with no indication of the manner of sealing or the grain orientation of the sealed wrapping.
Great Britain Patent 469,696, issued on Jul. 30, 1937, to American Marine & Foundry Company, describes a device for heat sealing folded bread wrappers. This patent does not show spatially adjustable heating elements, adjustable-speed conveyor belts, or the techinque of orienting polyethylene wrappers with a grain parallel to a long axis of a wrapped cylindrical object.
German Patent 2 203 976, issued on Aug. 2, 1973, to Werner Hoschele et al., describes a machine that forms open bags via heat sealing and closes the bags with metal clips. This patent does not show spatially adjustable heat-sealing elements, adjustable-speed conveyor belts, or the technique of orienting polyethylene wrappers with a grain parallel to a long axis of a wrapped cylindrical object.
None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed.